Centrifugal vibrator



Nov. 14, 1939.. 1y ASMUSSEN 2,179,807

GENTRIFUGAL VIBRATOR Filed Feb. 9,'1958 WWW/[Ill A Jes Asmussen INVENTORATTORNEY.

rented Nev. 14, w39

UNITED STATES oENrmrUcAr. vmmiron Jes Asmussen, Milwaukee', Wis.,assigner to A. 0.

Smith Corporation, Milwaukee, Wis., a corporation of New YorkApplication February 9, 1938, Serial No. 189,563

4 Claims. (Cl. 233-5) This invention relates to an improved apparatusfor classifying ores in which centrifugal force is applied toconcentrate particles having a high specilic gravity such as gold andprecious metals.

t In this machine the ore containing pulp is forced into riille grooves,the contour of which is changed at periodic intervals to vibrate theconcentrates and reclassify the particles deposited.

llt is anV object'of the present invention to prol vide an improvedmachine for concentrating ore particles.

A further object is to provide a concentrator with rimes lor collectingore particles, the contour of which may be changed by the application itof hydraulic pressureto agitate the concentrates.

Still another object is to provide a fluidcontainer dehning a rimesurface on one side thereof, which may be displaced by variations in theuid l pressure to either widen and narrow the grooves 2o between rimesor to lessen the depth of the riiile grooves.

Itis also the object of this invention to provide a centrifugalconcentrator with horizontal riilies arranged on the inside of the bowlwhich may be 2g periodically vibrated at intervals independent of thespeed of rotation of the bowl.

One embodiment of the invention is illustrated in the accompanyingdrawing which is a vertical cross sectional view of a rotary bowl, thesection au being taken along the axis of the bowl.

Referring to the drawing the bowl l is mounted on a vertical shaft 2journalled in any suitable uit i 'u t. The method of mounting androtating the bowl forms no part of this invention and l 3g the apparatusillustrated is intended to be more or less diagrammatic. Rotation of thebowl may be edected by a pulley t mounted on vthe shaft 2, driven by abelt 5 connected to any suitable power means.

M used around the inside of the bowl and suspended from the top where itis clamped between the danged rim t of the bowl and a ring l by means-of a number ofbolts 8 is a bellows 9 of ber or similar material. vTheouter wall of 4p the bellows lies Hush against the inner wall of thebowl, while the inner wall of the bellows is formed to provide a seriesof rimes extending around the bowl transverseto the bowl axis. The rimesleeve formed by the inside of the bellows must be ,5o hexible and forthis purpose rubber is well adapt- 55 having their inner faces attachedto the most exy tended portions of the riilles. The members I0 are morerigid than those sections ofthe riiiles which lie between the supportedportions and form the base of the rillie grooves. Accordingly thesemembers, when made of the same material 5 as the rimes, are thicker incross section than the base of the grooves, but it is contemplated thatthey may be the same thickness when made of harder material.

The cuter ends of the annular members l0 are l0 spaced a slight distancefrom the outer walls of the bellows to permit communication between thechambers created by such members. Notches may be' provided in the outerperiphery of the members l0 at various intervals to facilitate this 15communication.

The lowest rile is spaced some distance above the bottom of the bellowswith the result that there .is a fairly large sized chamber Il below thefirst rime-supporting annular member. The volume of iiuid contained inthis chamber must be maintained substantially constant and consequentlythe walls are preferably made of fabric which will resist expansion uponthe application of internal pressure.

Stretched across the bottom of the bowl and connecting the inner sidesof the bellows at a point a short distance below the first riilie is asheet l2, likewise of rubber or similar material. 'I'his sheet may beformed as a continuation of the inner wall of the bellows as illustratedin the drawing. Chamber Il is constructed below the riies and the sheeti2 in order that the pulp thrown out in the bowl 'will not impingeagainst the walls of the chamber to distort its contour or affect .35the pressure within the bellows. Consequently the external pressure onthe chamber ll will be maintained. at substantially uniform atmosphericpressure, and the variations in internal pressure .may be accuratelycontrolled.

packing to prevent leakage.

The pressure system just described may be economically operated withwater as the fluid medium. With a bowl adapted to be operated in theneighborhood of 1000 revolutions per minute, variations in fluidpressure are caused to occur at a rate of around 100 to 120 per minute.

Pulp is fed to the bowl by means of the centrally disposed feed pipe I1which discharges a slight distance from the bottom of the bowl. As thebowl is rotated the pulp is forced outwardly and upwardly over he riiliesurface surrounding the interior of the bowl and finally flows over thetop. Any suitable basin may be provided for discharged pulp such as atrough surrounding the bowl. No such means are shown because they areconventional and well known by those familiar with this art.

Ordinarily if the riile contour remained unchanged during theconcentration of the ore. particles of heavier specific gravity would bethrown into the grooves between riies together with sand and otherlighter undesirable particles. 'Ihis mass of particles soon becomessolidly packed in the grooves and further classification becomesimpossible.

By varying the pressure in thebellows, the contour of the riies may bechanged a number of times during the process to loosen up the particlesdeposited in the grooves and eventually to work the lighter particlesout of the bowl,

with the result that better classification ofheavier, desirableparticles can be obtained. Increasing the pressure lengthens the bellowsspreading the riles apart and creating a shallower, broader groove,which permits the pulp stream to sweep out lighter particles. At thesame time a broader surface is provided for the deposition of additionalheavier particles from the pulp stream.

When the pressure is decreased, the rimes resume their original positionand the grooves are deep and narrow, retaining heavier particles andexpelling lighter particles. Pressure impulses are controlled by thediaphragm pump entirely independent of the speed of rotation of the bowland may be varied for different ores and under different workingconditions.

The invention having been described what I claim and desire to secure byLetters Patent of the United States,'is:

1. In a rotary bowl for classifying materials of different specificgravities, a flexible sleeve defining a series of rlles arrangedtransversely to the bowl axis, said sleeve being disposed inside saidbowl and spaced therefrom, a fluid chamber between said riilies and thesides of the bowl, and means for changing the contour and width of theriilies by varying the ui pressure in said chamber. f r

2. In a rotary bowl for classifying materials of different specificgravities, a bellows of flexible material disposed around the inside ofthe bowl and adjacent the walls thereof, said bellows having a series ofriles arranged on the inner side thereof, fluid medium maintained withinsaid bellows, and means for varying the pressure of said uid medium tovaryl the contour and width of the riiiies.

3. A centrifugal concentrator which comprises a bowl, a flexible riiilesleeve disposed around the inside of the bowl and radially spacedtherefrom, a uid chamber between said riiile sleeve and said bowl,spaced annular members reenforcing said riiie sleeve and forming anumber of compartments in said fluid chamber, the, reinforcing memberscarried by said flexible riiiie sleeve being free to move axially uponthe lengthening or 'shortening of the sleeve, means for fluidcommunication between said compartments, and means for varying the fluidpressure within said chamber to flex the riiiies and agitate the oreparticles deposited in the riflies by varying the length of the sleeveand correspondinglyvarying the width of the riiiles. t

4. A centrifugal concentrator of the rotary bowl type which comprisesabowl, a bellows suspended inside said bowl, the inner surface of whichhas a series of riies arranged transversely to the direction of flow ofore pulp in the bowl, fluid medium maintained within said bellows, a

pump, and means for transmitting pressure impulses from said pump tosaid bellows to open and close the grooves between said riftles.

JES ASMUSSEN.

